Time to reset all the office screensavers to read "This is Temps' Week!", and send the same message across the network and intranet - this really is the week of the peripatetic worker. And if the employers haven't noticed, they will soon be reminded by all the secretarial agencies. Platoons of T-shirted consultants will descend on corporate offices all over the City of London, waving balloons and generally making a fuss of their temporary staff, just to make sure employers get the point.

There will even be a bus visiting five towns to do the same. To cap it all, on Friday one temp will go the Hilton in Park Lane to collect a priceless addition to a CV - the One in a Million award. This honours the best short-term contribution to a client's business, from nominations made by employers.

But behind the balloons, there are big differences over the temping world - there are rows and international court cases. Seven per cent of Britain's workforce are temps and 10% of female workers are in temporary jobs. Of our 1.7m contract workers across all industries and skills, a million introduce themselves to a new office environment every day. In the secretarial world, the figure is rising by 15% a year, and the number working through agencies has doubled in the past eight years.

However, the temp sector is polarising, says the TUC. At the top end is a new breed of highly skilled top-level professionals, temping by choice and playing the field for the highest money. But at the other end, two-thirds of these temps really want a permanent job, because of the benefits they miss. According to its report, Permanent Rights for Temporary Workers, it is economising on these benefits which makes temps so attractive to employers. The TUC believes that half of employers employing casuals pay them less than full-timers, many give no holiday pay, and most do not offer pension schemes.

As a result, the temps are "a growing band who are often paid less, have worse terms and conditions... trapped in temporary work which offers limited career opportunities, exclusion from work-related benefits, high levels of job insecurity and economic insecurity," says the report.

It sounds Dickensian, but the TUC may be pushing at an open door, says Ian Wolter of the Eden Brown agency. Wolter was on the Recruitment and Employment Confederation committee that devised Temps' Week.

Legislation dictates that after a qualifying period of 13 weeks, paid leave must be given. Eden Brown decided instead that their temps would qualify for paid leave from the moment they started working, at the rate of 8.16%. Thus, after the first day, a temp is probably entitled to half an hour off. After 13 weeks, the temp would have accrued five days paid leave. And after a year, 20 days. Wolter says that the agency slightly increased their rate to clients to pay for it, but "did not deduct anything from the temps' wages".

By 2004, temps will have the same rights as permanent staff thanks to the European directive on workers' rights, and a new directive on the temporary worker, he adds.

Lyn Cecil of Secretaries Plus, who was also on the REC committee, will be sending her T-shirted team out to clients' offices with coffee and croissants for the agency's temps. She is mildly exasperated with the picture of unfair temping.

"Some people who write those reports are stuck in the 1960s, and they certainly haven't met our temps. They ignore the fact that many people simply don't like being permanent; we've spoken to many employers about this, and they confirm that most temps simply aren't interested in their pension arrangements."

A real issue for the temp, says Richard Grace of the Gordon Yates agency, is in benefits accruing from a long contract period. "In a significant minority of companies, temps make up a sizeable part of the workforce, staying for up to a year or even longer, and ending up knowing more than the 'permanent' staff. Recruitment agencies need to look carefully at how they manage these long-term temps, in negotiating pay and performance reviews during a long-run tenure."

There has been big trouble over this inthe US. Long-stayers are known as "permatemps", and there have been several court cases where agency staff became valuable enough to be offered full-time positions - but were then told that their years' temping would not count towards their pensions.

At SmithKline Beecham, 1,000 employees went to court for retirement benefits involving permatemp work of up to 10 years, and at Microsoft, 2,500 workers are waiting for an appeal case that has been going on for two years, involving a variety of benefits including stock options. Seattle Central Community College co-ordinated 40 labour groups into an alliance for fair benefits for temps, and several cases have alleged that employers are using permatemps purely to avoid giving benefits. A similar case against a local authority in Oregon has now been going through the courts for six years.

Are temps good enough to deserve all this? At the end of the TUC report its says: "Employers also associate agency workers with higher absenteeism and view their performance as being unpredictable..."

That raised an eyebrow at the Eden Brown agency. It is still widely misunderstood, says Wolter, that a million clever people have simply chosen to work the temp way.

"We can see measurable examples of staff we have put in showing greater reliability than the permanent staff," he says. "An interesting comparison is that temps are expected to hit the ground running, whereas a permanent worker is expected to produce hardly anything in their first three or four days, going through induction. This is very unfair."

The ability of the temp is being powerfully argued by Qwiz, the "competence assessment" company which is backing the Temps' Week One in a Million awards. It was Qwiz which, back in the early days of PCs, first argued that the explosion of word-processing packages was causing problems for agencies who had previously assessed temps "with a speed-test and an egg-timer". Agencies could not afford to buy every piece of new software in order to assess their temps - so Qwiz produced simulated programmes that would go on the agency's computer network and offer just enough detail to allow a candidate to be tested and assessed.

Forty thousand agencies around the world now use the system, and most of Britain's temps will have gone through it without realising that they were not working on "real" installations. And now PAs can even go online and test themselves on www.qwizonline.com. Recognition of temps' ability is such a good idea that the Tate agency has been giving a monthly award for ages, says candidate services manager Katharine Wrathall.

"Recognition raises the overall appreciation of temps. Our clients are extremely interested to know how their nominee for a monthly award has fared - and if they are not successful, they want to know the reasons why?"